Help me interpret my injector test results!

[rennch]

Hi,

I've just pulled my injectors and tested their flow into water bottles. (my car is pretty much running on 4 cylinders, and am trying to track down why.)

Test results: Amount of fuel flowed is EXACTLY the same for all 6 cylinders. However, injectors 1 and 3 are throwing out some awful colored fuel.



For my next step I'm going to pull the hardlines to those two injectors and see if they are blocked. (but would they be blocked if they are sending the right amount of fuel?)

Any thoughts?

[timmy2]

My first thought is change the fuel filter and lines and try again.

[rennch]

Update. I had the same thought Timmy...so I switched a clean line for a dirty line, just to see. All six came out beautifully clear this time. So...I eliminated Fuel Delivery from the problem.

Back to spark.

What's the best way to test spark plug wires? Isn't there a screwdriver trick or something?

[rennch]

Ok...putting this one to bed. Ran a second test and the injectors are all even, and gas is the same color.

However, it looks like I'm getting very weak or no signal from cylinders 2 and 1. The mystery continues.

[T77911S]

i was going to say the fuel dist has corrosion in it. plus, run the test for a longer period. more fuel in the bottles gives you a better indication of volume differences. you can also run this test with the injectors removed.

have you checked the ground from the engine to the body?
what about the neg side of the coil to ground/CD unit?
have you put a meter on the battery with the engine running?
check ground at CD unit

[Rob T.]

Did you ckeck the connectors on your injectors?
Look like 1 and 3 did not work and because of that the fuel stays in the
valve and gets old.
I dont think its a ground problem..... because the other 2 injectors on the left
side are working and they get the same signal.

[boyt911sc]

Originally Posted by emptyo

Hi,

I've just pulled my injectors and tested their flow into water bottles. (my car is pretty much running on 4 cylinders, and am trying to track down why.)

Test results: Amount of fuel flowed is EXACTLY the same for all 6 cylinders. However, injectors 1 and 3 are throwing out some awful colored fuel.



For my next step I'm going to pull the hardlines to those two injectors and see if they are blocked. (but would they be blocked if they are sending the right amount of fuel?)

Any thoughts?

emptyo,

Volumetric test is one thing but the spray pattern for these injectors should be inspected too. The atomized fuel should look like a 'V' form mist/spray.

Tony

[Chuck.H]

Originally Posted by emptyo

Update. I had the same thought Timmy...so I switched a clean line for a dirty line, just to see. All six came out beautifully clear this time. So...I eliminated Fuel Delivery from the problem.

Back to spark.

What's the best way to test spark plug wires? Isn't there a screwdriver trick or something?

You can either watch your engine running on a very dark night and look for arc's, or (if you don't have a pacemaker) you can run your hands lightly over all the wires and feel for the arcs :-)

Chuck.H
'89 TurboLookTarga, 352k miles

[rennch]

They are all brand new wires though

[beepbeep]

Originally Posted by Rob T.

Did you ckeck the connectors on your injectors?
Look like 1 and 3 did not work and because of that the fuel stays in the
valve and gets old.
I dont think its a ground problem..... because the other 2 injectors on the left
side are working and they get the same signal.

This.

Two injectors don't seem to have fired and have accumulated old fuel.

What car?

[rennch]

Grabbed a compression test kit from Harbor Freight today. Will keep you posted.

[T77911S]

perhaps some more detail about the car.

CIS?

i have the HF compression tester too. i also have their leakdown kit. if you get it, replace the input gauge with one that reads 100psi.

that discolored fuel should tell you something. CIS, could be the fuel head getting corrosion in it.

[rennch]

I've moved the diagnosis of this thread to here: The mystery of my missing engine.